few_shots: Example:
Problem/activity:
Find the general solution for:
$${\mathrm{cos}\left({\pi\over2}+x\right)=\mathrm{tan}{\pi\over4}}$$


Standard options: 
A. Prove the Pythagorean identity sin^(2)(θ) + cos^(2)(θ) = 1 and use it to find sin(θ), cos(θ),or tan(θ) given sin(θ), cos(θ), or tan(θ) and the quadrant of the angle.
B. Prove the addition and subtraction formulas for sine, cosine, and tangent and use them to solve problems.


Thought: An initial step when solving for x in this problem requires the use of the addition formula for cosine on the left side of the equation. Solving this problem does not require use of the Pythagorean identity.
Answer: B

Now, assign the following problem or activity to one or more relevant standards it aligns with.
shot_info: fl_problem_001894

HS
options: Use rational approximations of irrational numbers to compare the size of irrational numbers, locate them approximately on a number line diagram, and estimate the value of expressions (e.g., p^(2)). For example, by truncating the decimal expansion of Ö2, show that Ö2 is between 1 and 2, then between 1.4 and 1.5, and explain how to continue on to get better approximations.

Know that numbers that are not rational are called irrational. Understand informally that every number has a decimal expansion; for rational numbers show that the decimal expansion repeats eventually, and convert a decimal expansion which repeats eventually into a rational number.
problem_activity: Problem 1
Write each rational number in the form
$${a\over{b}}$$
, where
$$a$$
and
$$b$$
are integers, and
$$b\neq0$$
.
a.
$${0.3333}$$
b.
$${-5.05}$$
c.
$${\sqrt{64}}$$
e.
$${\sqrt{4\over25}}$$
f.
$${\sqrt{1.21}}$$
Problem 2
A student wrote two repeating decimals as fractions using the strategy shown below.
| Given the decimal                       $$0.\overline{12}$$                       Let                       $$x=0.\overline{12}$$                       Then                         $$100x=12.\overline{12}$$              |https://d37su8u1z9ynie.cloudfront.net/uploads/2019/02/06/math8_u7_l5_ap2a.PNG|  |https://d37su8u1z9ynie.cloudfront.net/uploads/2019/02/06/math8_u7_l5_ap2a.PNG| image:: https://d37su8u1z9ynie.cloudfront.net/uploads/2019/02/06/math8_u7_l5_ap2a.PNG | Given the decimal                       $$0.\overline{123}$$                       Let                       $$x=0.\overline{123}$$                       Then                       $$1000x=123.\overline{123}$$             |https://d37su8u1z9ynie.cloudfront.net/uploads/2019/02/06/math8_u7_l5_ap2b.PNG|  |https://d37su8u1z9ynie.cloudfront.net/uploads/2019/02/06/math8_u7_l5_ap2b.PNG| image:: https://d37su8u1z9ynie.cloudfront.net/uploads/2019/02/06/math8_u7_l5_ap2b.PNG |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
a.   Describe the student’s strategy in your own words.
b.   Use the same strategy to write the two decimals below as fractions.
$${0.\overline{54}}$$
$${0.1\overline{23}}$$
Problem 3
What is the sum of
$${0.1}$$
and
$${0.\overline3}$$
written as a fraction?


correct_option_index: 1